Source tracking refers to a procedure where an angle is determined between a single antenna and a phased array of multiple antennas. The goal of a source-tracking estimation algorithm is to locate a source with respect to a phased array. Source tracking can be done using a phased array at a receiver and a single antenna at a transmitter. This configuration is known as Angle-of-Arrival (AoA). Source tracking can also be done using a phased array at a transmitter and a single antenna at a receiver. This configuration is known as Angle-of-Departure (AoD). The source-tracking estimation algorithms are also referred to as Time-Delay-of-Arrival (TDoA) or Direction-of-Arrival (DoA).